This is a Ding-kiln dish from the Jin dynasty, 12th century. It is 16 cm across, with incised lotus. Porcelain with a yellowish white glaze, classic teardrops on the back, glazed footrim with characteristic kiln grit. Two typical iron spots from polluted clay. Unglazed rim because of the upside down firing. The back shows the known knife marks . Slightly warped in shape, so likely a kiln waster.